Circuit breaker



. 1943- J. G. JACKSON 2,335,677

CIRCUIT BREAKER Filed Sept. 19, 1941 3 Sheets-Sheet l I I I I I I I I I l IN VEN TOR Nov. 30, 1943. J. G. JACKSON 7 2,335,677

CIRCUIT BREAKER Filed Sept. 19, 1941 s Sheets-Sheet 2 IN VEN TOR U01?! 6 Jackson Nov. 30, 1943. J. G. JACKSON 2,335,677

CIRCUIT BREAKER Filed Sept. 19, 1941 s SheetsSheet 3 IN VENTOR t/okiz G. r/acl'son Patented Nov. 30, 1943 PATENT OFFICE onwmr BREAKER John G. Jackson, Detroit, Micln, assiznor to Square B Company, Detroit, Mich, a corporation of Michigan Application September 19, 1941, Serial No. 411,519

- 17 Claims.

This invention relates to devices for making and breaking electrical circuits and has for its object the provision of an improved operating means for an automatic electric circuit breaker.

Another object of the present invention is to provide in an automatic electric circuit breaker an improved form of latching means for the releasable contact carrier.

Another object of the present invention is to provide in an automatic circuit breaker an improved latch and current responsive operating means therefor.

Another object of the present invention is to provide a multi-pole circuit breaker having improved operating means therefor.

Another object of the present inventlon is to provide a multi-pole circuit breaker having releasable contact carriers and current responsive latches therefor with means for releasing all the carriers upon an overload through one.

Other objects and features of the invention will be readily apparent to those skilled in the art from the following specification and appended drawings:

Figure l is a front-elevational view of the circuit breaker accordingto the present invention with the front cover partially broken away to show internal parts.

Figure 2 is a vertical sectional view taken on the line II-Il of Figure 1.

Figure 3 is a vertical sectional view taken on the line III-III of Figure 1. I

Figure 4 is a view similar to Figure 3, but with the contacts shown in separated position.

Figure 5 is a view similar to Figure 2, but with the operating parts shown in manual oil and/or reset position. 1

Figure 6 is a view similar to Figure 2, but with the parts in overload tripped position.

The circuit breaker as illustrated in the drawings comprises an outer enclosing box. 5 having a cover 2 mounted thereon. Within the box and upon the back wall 3 thereof is mounted a generally cup shaped insulating base a having a pair of dividing Walls 5 and 5 to provide three com partments therein. A metallic cover i is preferably sealably attached to the base t by means of spunover portions of rivets or in any other manner and an insulating sheet 8 of fibre or other material is disposed in back of the metallic cover I.

Within the central compartment E there is provided a latch H for a purpose to be hereinafter described, slideably supported upon a gen- 5 movable member I2 and shoulder surfaces i5 on the latch and continually biases the latch for movement toward the lower end of the base t and away from leg [4. A cotter pin it carried by the latch l 1 determines its normal extended posi- 10 tion. A second spring ll interposed between the back wall l8 of the base and an extension is of the movable member l2 continually biases the member for movement forwardly toward the front of the base.

Upon a shaft 2| received within notches in the dividing walls 5 and B is mounted a rotary handle 22 having an interior camming surface adapted to cooperate with the flat front surface of the rectilinearly movable member l2 and including a zo stable contacts engaged flat surface 23.

The latch H is biased by spr ng l3 to releasably engage a surface of a movable member 24 which is guided for rectilinear movement at right angles to the back of the base by slots formed 2 within the opposing dividing walls 5 and 6. The

member 24 is adapted to extend through these slots and into the compartments 25 and 25 provided at either side of the central compartment 9. Fibre plates 21 and 28 are disposed at either 36 end of the central compartment 9 to sealably enclose it against access.

Within the compartments 25 and 2d are disposed similar individual circuit breaker mechanisms embodying a floating contact bar or switch member 29 having a notch 3i in its front edge receiving the front edge of a cooperating slot provided in the longer leg of a generally s shaped member 32. A spring 33 engages the under side of the contact bar 29 and exerts its force there- 4 through to maintain the member forwardly and to bias the contact bariQ for clockwise movement about its pivotal engagement with member 32. A stud 35 is provided upon the night portion of the U shaped member 32 engageable with the front of the base to limit forward movement of the so tilinearly movable member 2 3 and movable therewith.

Upon an end ledge 3i at the top of the circuit breaker is mounted a connector to as by means of a spun over portion of a metallic insert erally L shaped member l2 which is guided for 33. A terminal stud ti is provided threaded into which is provided with a slot 41 closely receiving the contact bar 29 which extends through the slot into the arc chamber whereby the movable contact surface 34 may cooperate with the stationary I 7 contact 42. a

At the bottom end of the circuit breaker and upon a ledge 48 is mounted a connector 49 as by means of a spun over portion 01' a metallic insert having a terminal stud 52 threaded therein. The connector 49 extends within the interior of the breaker and has its central interior end pressed out as at 53 and to this end is rigidly secured as by welding a current responsive bi-metallic strip 54. A stud 55 carried by the connector 49 presses against the pressed out portion 53 and serves to adjust the position of the bi-metal and hence the current rating to which the breaker is responsive. A flexible lead 58 connects the free end of the bi-metallic member 54 to the contact bar 29. Rigidly secured to the latch II as by welding are two oppositely directed L shaped members 51 adapted to extend through slots 58 provided in the walls 5 and 6 and into compartments 25 and 25. The members 51 are provided with flanges 59 extending toward the back of the base 4 and carrying insulating buttons 6| adapted to be engaged by the bi metallic members 54 whereby movement of either of the bi-metallic members 54 when heated will effect movement oi the latch Hinto unlatching position. Insulating walls 62 serve to seal off the bottom of the breaker from the exterior.

The operation of the circuit breaker will now be described. As specifically shown herein, the circuit breaker is of the mnl tnpole form and the individual circuit breaker mechanisms will perform simultaneously. As illustrated in Figures 2 and 3, the circuit breaker is in the closed circuit position. To place the parts in manna fofl position, the handle 22 is rotated in clockwise direction until the surface 23 is disengaged from the front surface of the movable carrier member i2 whereby the force exerted by spring ill will force both the member 52' and the latch ii supported thereon rectilinearly forward toward the front of the base. it away from the rectilinearly movable member 24 releases the restraining force thereon so that the force exerted by the compression springs 93 is free to efiect clockwise rotation of the contact bars 29 to simultaneously'separate the contact surfaces 34 from the contact surfaces 42. Through its engagement with the contact bars 29 the movable member 24 will be moved rectilinearly forwardly toward the front of the base by the springs 33 until the upper portion of the member 24 is engaged by the insulating liner 8 whereby all further movement of the circuit breaker parts will be halted. Thus it is seen that the-removal of the restraint of handle 22 upon the latch I l provides for simultaneous movement of both contact bars 29 to simultaneously break both poles of the breaker. To again place the parts in closed circuit position the handle is This movement oi. the latch rotated in a counterclockwise direction whereby latch i I will be moved to positively move member 24 and contact bars 29 into contacts engaged position.

Upon the occurrence of an overload through either of the bi-metals 54 it will become heated and bend counterclockwise as viewedin Figure 3. In this movement it pushes uponthe insulating button 8! to rectilinearly move latch l'l against the bias of spring Hi to disengage the latch from the rectilinearly movable member 24. When the member 24 is released the contact bars'29 are then free to simultaneously rotate about their pivotal engagement with the member 32 and under the bias of compression spring 33 and to rectilinearly move the member 24 into the position shown in Figure 6.

To reset the breaker the operating handle 22 is rotated clockwise to o position whereby spring I! will effect a rectilinear movement of the supporting member I2 to carry the latch II in a like direction to a position where the compression spring l3 can act to effect rectilinear movement of the latch in a direction substantially at right angles to the direction of movement efiected by spring i1 and into re-engagement with the rectilinearly movable member 24.

It isto be noted that the rectilinearly movable member 24is made sufliciently long so that when the front edge thereof engages the front oi the base, the latch engaging surface 20 thereon will b stopped in a position to which the latch H may be readily moved by springs i3 to effect reengagement therewith after an overload release has occurred.

While certain preferred embodiments of the invention have been specifically disclosed, it is understood that the invention is not limited thereto as many variations will be readily apparent to those skilled in the art and the invention is to be given its broadest possible interpretation within the terms of the following claims.

What is claimed is:

1. In an automatic electric circuit breaker, a stationary contact, a movable member having a contact surface adjacent to one and adapted to cooperate with said contact, an actuating member, means biasing the opposite end of said movable member into engagement with said actuating member, a relatively fixed pivot for said movable member interjacent said biasing means and contact surface, manual means operative upon said actuating member to move said movable member against said biasingmeans to contacts engaged position and current responsive means mounted independently of said movable member to effect automatic movement of said movable member to contacts separated position.

2. In an automatic electric circuit breaker, a stationary contact, a movable contact bar carrying a contact surface adjacent one end adapted to cooperate with said contact, means biasing said movable contact toward disengaged position, a movable element engaging the opposite end of the bar, manual means operative on said movable element to move said bar against said biasing means to contacts engaged position, and current responsively controlled latching means independently mounted of said contact bar, and releasably engageable with said movable element, said bar being movable to contacts disengaged position upon release of said movable element by said latching means on the occurrence of an overload.

3. In an automatic electric circuit breaker, a

stationary contact, an elongated member carry ing a contact surface adjacent to one end ted to cooperate with said contact, a relatively fine-i pivot for said elongated member, at .veotilineesiy movable member engaging the opposite enrl of the eiongated member, operative to move said elongated member seiei pivot to com seitl n, is as member and operable on force means to effect movement saici svvitc, to contacts separated position.

5. in an automatic electric circuit stationary contact, a movable svv; having a contact surface one end the relatively fixed pivot therefor, means ate the ends of the switch member biesir toward contacts disengaged position, ectu: means engaging the opposite encl oi the sv member for moving said switch member st said biasing means to efieet engagement of contacts whereby said biasing mes-ins becomes it: operative upon said switch member to pr vide substantial pressure between said cent current responsive means monnteei ind ly of said switch member and ccoperat st to move 7e movement of said first rectilineeriv ovebie member and of said contact member lets en aged position, and current responsive for moving said seconci rectilinearly movto rel-ease said first rectilineariy s'iicl contact member moving c sengaged position irrespective o' -:it supporting element upon res i rec linearly movebie L35? o automatic electric circuit tact, a movable contact, co

to move said movable 8Z1QSH1E-it one disengagement with s 5o vary con ring means eontinuoll, .e

i i see toward disengaged nosi movable so member, rectilineeriy m lg operative engagement aici contact member, a movable latch siieleeb switch member by said biasing means disengageol position.

6. In an automatic electric stationery contact, a switch move said movable contact in gagement with said stationery con linearly movable member opeietivei said switch member, a movable lets. with said rectilinearly movobie i for moving said latch rectilineeriy to positively move said rectilinearly movable anei se with sald lacbilmearly flv e merry switch member to contacts engegefi position, and a $590115?- Spline means cmlfiinualii b asing current responsive means for moving said iotch 53-35! toward l a ed position, manual rectilinearly but in a direction at right angles to @Qemtive acbllafle Said Suppo t ember aid first path f movement t l m n. on "to move said latch to effect positive movement lineal-1y mevable member effeci; am rectilinearly movable member and of said of said switch member to contacts tiisengeged contact member to contacts engaged posibien, position and current responsive means for moving said 7. In an automatic electric circuit breaker, y d in a direction oth r stationary contact, a movable contact, a switch member movable to move said movable contact to engaged and disengaged positions, biasing" iearlv movable member to effect movement contact member to contacts disengaged means for said switch member, a rectiiineariy position under the bias of said first spring means movable member operativeiv engaging saia independently of any movement of said sunswitch member, a movable latch engageoble with 70 port said rectilinearly movable member, spring means ii. In automatic electric circuit breaker, continually biasing said latch toward engaged stationary contact, a. movabie contact, a contact position, means for mflving d lei/61! rectiliilmember movable to move said movable contact y o Positively mOVe Said r lineerlv m0vfor cooneretion with said stationary contact to able member and Said Switch member b cont-116E 7 make and break an electric circuit theret'nrcngii,

a rectilinearly movable member having operative engagement with said contact member, spring means continually biasing said contact member toward disengaged position, a movable support member, a rectilinearly movable latch slideably carried by said movable support and having engagement with said rectilinearly movable member, a second spring means continually biasing said rectilinearly movable latch toward engaged position, manual means operative to ON position for actuating said movable carrier member to rectilinearly move said latch to effect positive movement of said rectilinearly movable member and of said contact member to contacts engaged position, a third spring mean operative upon said support member for movement thereof toward contacts disengaged position upon movement of said manual means to OFF position, and current responsive means for moving said latch rectilinearly and in a direction substantially at right angles to its first path of movement and against the bias of said second spring means to release said rectilinearly movable member for effecting movement of said contact member from contacts ngaged-to contacts disengaged position under the bias of said first spring means and independently of any movement of said support member.

12. In an automatic electric circuit breaker, a

' stationary contact, a movable contact, a switch member movable to move said movable contact for cooperation with said stationary contact to make and break an electric circuit therethrough, a rectilinearly movabl member having an operative engagement with said switch member, biasing means for said switch member and said rectilinearly movable member, a movable latch having engagement with said rectilinearly movable member, manual means operable to ON position to move said latch rectilinearly to positively move said rectilinearly movable member to actuate said switch member to contacts engaged position, and current responsive means for moving said latch rectilinearly to release said rectilinearly movable member, said rectilinearly movable member and said switch member moving under the force of said biasing means to contacts disengaged position when said rectilinearly movable member is released, and spring meansadapted to move said latch into reengagement with said rectilinearly movable member upon movement of said manual means to OFF position.

ment with said switch member and being engaged by said latch, a manual operator operable to ON position to move said carrier and said latch rectilinearly for positively actuating said rectilinearly movable member and said switch member to contacts engaged position, and current responsive means" for moving said latch rectilinearly to release said rectilinearly movable member, said switch member moving to contacts disengaged position upon release of said rectilinearly movable member, spring means operable to move said carrier and said latch rectilinearly and in a reverse direction to said first direction of movement upon movement of said manual operator to OFF position and a second spring means operable to move said latch rectilinearly and at right angles to said path of reverse movement into reengagement with said rectilinearly movable member.

14. In an automatic electric circuit breaker, a stationary contact, a movable switch member having a contact surface adjacent to on end adaptedto cooperate with said stationary contact, a slideably mounted force applying means engageable with the opposite end of said switch member for efiecting positive movement thereof to contacts engaged position, biasing means intermediate the ends of said switch member, manual means for moving said force applying means, a relatively fixed pivot for said switch member, and a member automatically operable on current overloads and normally engaging said force applying means and releasable therefrom on current overloads to effect movement of said switch member about said pivot.

15. In an automatic lectric circuit breaker,

. a stationary contact, a movable switch member having a contact surface adjacent to one end adapted to cooperate with said contacts, actuating means engaging the opposite end thereof for effecting positive movement of the switch member to contacts engaged position, a relatively fixed pivot for said member; biasing means for said member intermediate the pivot and said opposite .end, and means for effecting manual movement of said movable switch member against said biasing means to contacts engaged position, said means including a member mounted independently of said switch member and normally engaging said actuating means and being automatically movable on the occurrence of current overload to release said actuating means.

16. In an automatic electric circuit breaker, a stationary contact, a contact bar carrying acontact surface at one end adapted to cooperate with said stationary contact, an actuating member for effecting movement of said contact bar to ON position, means intermediate the ends of the bar biasing the opposite end thereof into engagement with said actuating member, a rectilinearly movable latching member normally engaging said actuating member during manual operation, and being automatically movable out of engagement therewith on the occurrence of a current overload, and fixed means engaging said bar, said bar being freely rotatable relative to said fixed means upon release of said actuating member from said latching member.

17. In an automatic electric circuit breaker, a stationary contact, a switch member having a contact surface adjacent to one end adapted to cooperate with said stationary contact, a movable member operatively engaging the opposite end of said switch member for efiecting movement thereof to the ON position, a relatively fixed pivot for said switch member, a rectilinearly movable latch automatically operable in response to current overloadnormally releasably ngaging said movable member, and manually operable means efieoting positive movement of said latch to actuate said movable member to positively move said switch member to contacts engaged position.

JOHN G. JACKSON. 

